/**
<p>编写一个程序，通过填充空格来解决数独问题。</p>

<p>数独的解法需<strong> 遵循如下规则</strong>：</p>

<ol> 
 <li>数字&nbsp;<code>1-9</code>&nbsp;在每一行只能出现一次。</li> 
 <li>数字&nbsp;<code>1-9</code>&nbsp;在每一列只能出现一次。</li> 
 <li>数字&nbsp;<code>1-9</code>&nbsp;在每一个以粗实线分隔的&nbsp;<code>3x3</code>&nbsp;宫内只能出现一次。（请参考示例图）</li> 
</ol>

<p>数独部分空格内已填入了数字，空白格用&nbsp;<code>'.'</code>&nbsp;表示。</p>

<p>&nbsp;</p>

<div class="top-view__1vxA"> 
 <div class="original__bRMd"> 
  <div> 
   <p><strong>示例 1：</strong></p> 
   <img src="https://assets.leetcode-cn.com/aliyun-lc-upload/uploads/2021/04/12/250px-sudoku-by-l2g-20050714svg.png" style="height:250px; width:250px" /> 
   <pre>
<strong>输入：</strong>board = [["5","3",".",".","7",".",".",".","."],["6",".",".","1","9","5",".",".","."],[".","9","8",".",".",".",".","6","."],["8",".",".",".","6",".",".",".","3"],["4",".",".","8",".","3",".",".","1"],["7",".",".",".","2",".",".",".","6"],[".","6",".",".",".",".","2","8","."],[".",".",".","4","1","9",".",".","5"],[".",".",".",".","8",".",".","7","9"]]
<strong>输出：</strong>[["5","3","4","6","7","8","9","1","2"],["6","7","2","1","9","5","3","4","8"],["1","9","8","3","4","2","5","6","7"],["8","5","9","7","6","1","4","2","3"],["4","2","6","8","5","3","7","9","1"],["7","1","3","9","2","4","8","5","6"],["9","6","1","5","3","7","2","8","4"],["2","8","7","4","1","9","6","3","5"],["3","4","5","2","8","6","1","7","9"]]
<strong>解释：</strong>输入的数独如上图所示，唯一有效的解决方案如下所示：
</pre>
  </div>
 </div>
</div>

<img src="/ https://assets.leetcode-cn.com/aliyun-lc-upload/uploads/2021/04/12/250px-sudoku-by-l2g-20050714_solutionsvg.png" style="height:250px; width:250px" />

<p>&nbsp;</p>

<p><strong>提示：</strong></p>

<ul> 
 <li><code>board.length == 9</code></li> 
 <li><code>board[i].length == 9</code></li> 
 <li><code>board[i][j]</code> 是一位数字或者 <code>'.'</code></li> 
 <li>题目数据 <strong>保证</strong> 输入数独仅有一个解</li> 
</ul>

<div><div>Related Topics</div><div><li>数组</li><li>哈希表</li><li>回溯</li><li>矩阵</li></div></div><br><div><li>👍 1918</li><li>👎 0</li></div>
*/

//leetcode submit region begin(Prohibit modification and deletion)
class Solution {
    public void solveSudoku(char[][] board) {
        
    }
}
//leetcode submit region end(Prohibit modification and deletion)
